Leaking injector questions
10-14-2009, 03:46 PM
#16
Race Car
I still have trouble with warm starts, but like Dan I have more cranking encrichment.
I'm still fiddling with it. It's tough to chase down, because you really only get one chance to crank the car. If it starts, great. If not, the next crank you're no longer dealing with the original state you're trying to correct. So it makes it harder to figure out whether it's too lean or too rich.
Not to thread hijack, but Dan what's the rationale behind setting 36lb instead of 42lb, when running 42lb?
BTW, I set my cruise map in open loop a fair bit richer to compensate for the leanout I was experiencing on warm days with a heat soaked engine. Now that it's cooler in San Diego, the o2 adjustment is maxing out at -20% on some cells, indicating the map is too rich to fully correct. Temps really seem to have a lot to do with variance in the AFR. Maybe this is obvious to everyone else, but it's something else for me to think about...I would think cooler, denser air would have to somewhat counteract having cooler, denser (?) fuel, but it definitely isn't a linear relationship.
I'm still fiddling with it. It's tough to chase down, because you really only get one chance to crank the car. If it starts, great. If not, the next crank you're no longer dealing with the original state you're trying to correct. So it makes it harder to figure out whether it's too lean or too rich.
Not to thread hijack, but Dan what's the rationale behind setting 36lb instead of 42lb, when running 42lb?
BTW, I set my cruise map in open loop a fair bit richer to compensate for the leanout I was experiencing on warm days with a heat soaked engine. Now that it's cooler in San Diego, the o2 adjustment is maxing out at -20% on some cells, indicating the map is too rich to fully correct. Temps really seem to have a lot to do with variance in the AFR. Maybe this is obvious to everyone else, but it's something else for me to think about...I would think cooler, denser air would have to somewhat counteract having cooler, denser (?) fuel, but it definitely isn't a linear relationship.
Brian, the reason I put 36lb injectors in the parameters screen (and I've heard others doing the same) is because at 42lb, I can't get enough adjustment range. The values are too large and at the high load areas I hit 127.
Dan
'91 928GT S/C
475hp/460lb.ft
10-14-2009, 04:16 PM
#17
Rennlist Member
Can't think of any reason for that, but it may be a USB communication issue. Sometimes just restarting the datarun can help that aspect.
Try restarting ST and see if the EZK system monitor works..... or try another USB port if one is available.
Not seen these problems here though. Maybe due to low volts at start ?
Try restarting ST and see if the EZK system monitor works..... or try another USB port if one is available.
Not seen these problems here though. Maybe due to low volts at start ?
Any reason i should see a discrepency between whats data logged on the LH vs the EZK for throttle postion?
During my first start this AM (which it FN didnt by the way) a few seconds into the start the EZK jumps to a throttle postion of "2" (cruise) while the LH data shows "1" idle.
The TPS checks out when i pull up the "fuel system monitor" screen and press the acclerator...
On the "igntion system monitor" screen it shows "cruise" and doesnt move when i press the accelerator.??
I tell ya what though, my poor battery is going to be toast when this gets solved!! Becasue of all this ive wired in a Hella quick disconnect instead of the wing nut....very handy for when you have to charge it several FN times a day !!!
During my first start this AM (which it FN didnt by the way) a few seconds into the start the EZK jumps to a throttle postion of "2" (cruise) while the LH data shows "1" idle.
The TPS checks out when i pull up the "fuel system monitor" screen and press the acclerator...
On the "igntion system monitor" screen it shows "cruise" and doesnt move when i press the accelerator.??
I tell ya what though, my poor battery is going to be toast when this gets solved!! Becasue of all this ive wired in a Hella quick disconnect instead of the wing nut....very handy for when you have to charge it several FN times a day !!!
10-15-2009, 02:10 AM
#18
Three Wheelin'
Tony, I think you need to richen things up. I moved richer towards what Dan posted earlier today and my car fired up easier than before. I think he's on to something.
10-15-2009, 04:34 PM
#19
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If you could Brian, email me the basics of your paramters screen (whats in RED) and your "warm cranking map". Actually anyone running 42lbs injectors and has good warm/hot start consistancy!
id like to get on the same page as some whose car atleast starts at this point!
10-15-2009, 04:49 PM
#20
Three Wheelin'
I updated it yesterday:
42lb/hr Injectors
.94MS
6900
3.2 cranking pulse width
There are 15 cells on the cranking fuel map:
94
82
58
46
36
28
17
14
14
10
7
5
4
2
0
I think this is similar to Dan's and it seems to have helped on warmer starts.
42lb/hr Injectors
.94MS
6900
3.2 cranking pulse width
There are 15 cells on the cranking fuel map:
94
82
58
46
36
28
17
14
14
10
7
5
4
2
0
I think this is similar to Dan's and it seems to have helped on warmer starts.
10-15-2009, 10:32 PM
#24
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using those parameters above!
only issue is now my WOT map is based on a different injector size and pulse width...
Some higher math may be in order to figure out my cranking map/pulse with with an injector size of 38.6 (my WOT map is based on this...and i DO NOT want to go back to triple digit 150mph plus speeds again to tune it)
bottom line is..it appears i needed to go RICHER at start? 180' of what i am thinking and thought i was seeing?
Thanks Brian...and DAN, you are not on my ignore list..i referenced your warm up map on a few other start attempts. Trust me,. i take alll the info i get on here and use it!!
...DAYUM...just started again!!!
defintiely rich...but started with little or NO hesitation!
Ill play around more on Monday...gotta work this weekend, unfortunately.
oddd thing is, it used to start fine with my original settings on 110'F days (airtemp)...coolant north of 210ish!! ???? I dont recall ever saving anything that could have cause my tune to change....especially between a fill up?
10-16-2009, 12:16 AM
#25
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....an hour later...It starts again!!!
This is SUCH a relief!..ive tossed some time, frustration and $$$$ at this!..next thing was a match!
Time for a
if i can adjust things now where i can keep my same injector size that i tuned with under WOT and the rest of the map i wil lbe VERY happy.
This is SUCH a relief!..ive tossed some time, frustration and $$$$ at this!..next thing was a match!
Time for a
if i can adjust things now where i can keep my same injector size that i tuned with under WOT and the rest of the map i wil lbe VERY happy.
10-16-2009, 12:27 AM
#27
Race Car
Here's another thing I am learning. When the car is cranking, that's one thing. You need to fatten up the cranking map to get it to start. However, like 0.5 seconds after it is running, it's a whole different ball game. My car starts fine but then immediately goes very rich and the idle oscillates up and down until the O2 sensor comes online, then it settles down. It's kinda funny, because it will start and settle on a perfect 775 idle, then start the oscillation. This only happens when the car is warm, cold starts are no problem. If I lower the cranking map and/or cranking pulse width values, it takes more cranking to start and still does the same oscillating, so I don't think those values have anything to do with the problem. Another funny thing is that when the O2 compensation begins, it starts at a high negative number, but after 20 seconds or so settles around 0, so that says to me that my base idle values are good. My warmup map in that temp region is all 0's too. I wonder what is telling the LH to put so much fuel in there... I've pretty much nailed down everything on my car thanks to the ST2, except this one.
Dan
'91 928GT S/C 475hp/460lb.ft
Dan
'91 928GT S/C
475hp/460lb.ft
10-16-2009, 02:47 PM
#28
Three Wheelin'
What I have found is that during the time from start to when the o2 sensor comes on line, the car goes really rich, but needs to stay really rich. If I lower the warmup enrichment, I get a lot of lumpyness as I pull out of a parking place or whatever. This is even an normal operating temps.
So I have kept mine much richer than it seems like I should during that minute or so.
So I have kept mine much richer than it seems like I should during that minute or so.
11-19-2009, 06:06 PM
#29
Three Wheelin'
Here's another thing I am learning. When the car is cranking, that's one thing. You need to fatten up the cranking map to get it to start. However, like 0.5 seconds after it is running, it's a whole different ball game. My car starts fine but then immediately goes very rich and the idle oscillates up and down until the O2 sensor comes online, then it settles down. It's kinda funny, because it will start and settle on a perfect 775 idle, then start the oscillation. This only happens when the car is warm, cold starts are no problem. If I lower the cranking map and/or cranking pulse width values, it takes more cranking to start and still does the same oscillating, so I don't think those values have anything to do with the problem. Another funny thing is that when the O2 compensation begins, it starts at a high negative number, but after 20 seconds or so settles around 0, so that says to me that my base idle values are good. My warmup map in that temp region is all 0's too. I wonder what is telling the LH to put so much fuel in there... I've pretty much nailed down everything on my car thanks to the ST2, except this one.
Dan
'91 928GT S/C 475hp/460lb.ft
Dan
'91 928GT S/C
475hp/460lb.ft
11-19-2009, 06:27 PM
#30
Race Car
Dan
'91 928GT S/C
475hp/460lb.ft